code: def ssd_512_vgg16_atrous_voc(
      pretrained=False, pretrained_base=True, **kwargs
  ):
      """SSD architecture with VGG16 atrous 512x512 base network.
  
      Parameters
      ----------
      pretrained : bool or str
          Boolean value controls whether to load the default pretrained weights for model.
          String value represents the hashtag for a certain version of pretrained weights.
      pretrained_base : bool or str, optional, default is True
          Load pretrained base network, the extra layers are randomized.
  
      Returns
      -------
      HybridBlock
          A SSD detection network.
      """
      classes = VOCDetection.CLASSES
      net = get_ssd(
          "vgg16_atrous",
          512,
          features=vgg16_atrous_512,
          filters=None,
          sizes=[51.2, 76.8, 153.6, 230.4, 307.2, 384.0, 460.8, 537.6],
          ratios=[[1, 2, 0.5]]
          + [[1, 2, 0.5, 3, 1.0 / 3]] * 4
          + [[1, 2, 0.5]] * 2,
          steps=[8, 16, 32, 64, 128, 256, 512],
          classes=classes,
          dataset="voc",
          pretrained=pretrained,
          pretrained_base=pretrained_base,
          **kwargs,
      )
      return net
  
imports: from __future__ import absolute_import
  import warnings
  from .ssd import get_ssd
  from .anchor import LiteAnchorGenerator
  from .vgg_atrous import vgg16_atrous_300, vgg16_atrous_512
  from ...data import VOCDetection
label_desc: Use image node_id 4 for calling a global function with example usage: ssd_512_vgg16_atrous_voc(pretrained, pretrained_base) and returns: net